按位"与"运算.
BitAND ( 值1, 值2 [, 值 n] )
Local $x = BitAND(13, 7) ;x == 5 ,因为 1101 AND 0111 = 0101 $x = BitAND(2, 3, 6) ;x == 2 ,因为 0010 AND 0011 AND 0110 = 0010